Abstract/Summary

process-based model of the energy crop Miscanthus×giganteus is integrated into the global climate impact model IMOGEN, simulating the potential of large-scale Miscanthus plantation to offset fossil fuel emissions during the 21st century. This simulation produces spatially explicit, annual projections of Miscanthus yields from the present day to the year 2100 under an SRES A2 anthropogenic emissions scenario and includes the effects of climate change. IMOGEN also simulates natural vegetation and soil carbon storage throughout the 21st century. The benefit of Miscanthus cultivation (avoiding fossil fuel emissions of CO2) is then compared with the cost of displacing natural vegetation (carbon emissions from vegetation and soil). The time taken for these effects to cancel out, the pay-back time, is calculated regionally. The effects of large-scale Miscanthus plantation are then integrated globally to produce an estimate of atmospheric CO2 concentrations throughout the 21st century. Our best estimate of the pay-back time for Miscanthus plantation is 30 years. We project a maximum possible reduction in atmospheric CO2 of 323 ppmv by the end of 21st century, with a reduction of 162 ppmv corresponding to the best estimate scenario.